Icings were investigated near the Tibbitt to Contwoyto Winter Road to examine the relation of overflow timing to air and ground temperature, rainfall, and winter road construction. Icings developed
before the end of active-layer freezeback by intermittent overflow of water from upstream lakes. Open-system freezing in saturated peat caused build-up of hydraulic pressure, leading to overflow. The active layer remained hydrologically active after
the overflow period. The duration of the overflow period was positively related to autumn rainfall. As the hydrological regime in the Canadian Shield is moderated by bedrock thresholds, icing development depends on basin catchment size and antecedent
conditions.

Summary

(Plain Language Summary, not published)This paper investigates icings near the Tibbitt to Contwoyto Winter Road, near Yellowknife, NT. Icings are a mass of layered ice that forms from
successive overflows of water onto the ground or ice surface in winter. The relation between the timing of overflows and air and ground temperature, rainfall, and winter road operation are examined.